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Updated: Jun 29, 2026
08:51
Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
Published on: February 19, 2021
Fast three-dimensional 1H MR spectroscopic imaging at 7 Tesla using "spectroscopic missing pulse--SSFP"
Christian Schuster1, Wolfgang Dreher, Jörg Stadler
1University of Bremen, FB 2 Chemistry, Bremen, Germany.
Magnetic Resonance in Medicine
|October 7, 2008
Summary
Spectroscopic Missing Pulse--SSFP (spMP-SSFP) enables fast 3D proton MR spectroscopic imaging (MRSI) at 7 Tesla. This technique allows detection of key brain metabolites in healthy volunteers within minutes.
Area of Science:
- Magnetic Resonance Imaging
- Neuroimaging
- Spectroscopy
Background:
- Proton MR spectroscopic imaging (MRSI) provides valuable metabolic information.
- Previous studies were limited by lower field strengths (3T).
- High-field (7T) MRSI offers improved spectral resolution but faces hardware and safety challenges.
Purpose of the Study:
- To demonstrate the feasibility of fast 3D proton MR spectroscopic imaging (MRSI) at 7 Tesla using spectroscopic Missing Pulse--SSFP (spMP-SSFP).
- To adapt the spMP-SSFP sequence for 7T hardware limitations, including specific absorption rate (SAR) and radiofrequency (RF) field strength.
- To assess the capability of the developed sequence for detecting key brain metabolites.
Main Methods:
- Implementation of spMP-SSFP sequence with modifications for 7T.
- Inclusion of two spatially selective RF pulses and a dual-band chemical shift selective RF pulse for water and lipid suppression.
- Acquisition of 3D MRSI data from healthy volunteers.
Main Results:
- Successful fast 3D MRSI measurements were achieved within approximately 8.5 minutes.
- The sequence enabled detection of major brain metabolites: N-acetyl aspartate, total creatine, choline, myo-inositol, and glutamate+glutamine.
- Nominal and real voxel sizes were 0.62 cm³ and 2.6 cm³, respectively.
Conclusions:
- The spMP-SSFP sequence is suitable for rapid 3D proton MRSI at 7T.
- Sequence modifications successfully addressed 7T-specific hardware and safety constraints.
- This technique facilitates in vivo metabolic imaging of the brain at high field strengths.
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